ECT is considered for people with depression who have not had success with medication and psychotherapies. VNS is approved by the FDA as an adjunctive therapy for partial-onset epilepsy and treatment-resistant depression, although controversial because results of studies testing its effectiveness in treating major depression have been mixed. rTMS was approved for use by the FDA as a treatment for major depression for patients who have not responded to at least one antidepressant medication. It is also used in countries such as in Canada and Israel as a treatment for depression for patients who have not responded to medications and who might otherwise be considered for ECT. Deep brain stimulation (DBS) was first developed as a treatment for Parkinson's disease to reduce tremor, stiffness, walking problems and uncontrollable movements. So far, very little research has been conducted to test DBS for depression treatment, but the few studies that have been conducted show that the treatment may be promising.